Question: "Which is {musical key} of {Piano Concerto}, whose {prequel is} is {D minor} ?"
Paraphrase: "Which is {musical key} of {Piano Concerto}, whose {prequel is} is {D minor} ?"
SPARQL (Wikidata): SELECT ?answer WHERE { wd:Q44261 wdt:P826 ?answer . ?answer wdt:P155 wd:Q283903}
Answer: A minor